Bark-cutting machine



. 2 Sheets-Sheet -1. $.13. THOMPSON 85S. W. JOHNSON.

Bark Cutting MaohineQ No. 229,205. Patg ntgd. June 22, 1330.

N-PETERS. PHOTCLUTHOGRAFNER, WA5N|NGTON D C 2 Sheets-Sheet 2. S. R. THOMPSON & S. W. JOHNSON.

Bark Gutting. Ma0hine. No. 229,205. Patented June 22,1880.

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SAMUEL R. THOMPSON, OF BROOKLINE, AND-SAMUEE WV. JOHNSON, OF

WEST MEDFORD, MASSACHUSETTS.

BARK-CUTTING MACHINE.

SPECIFICATION forming part of Letters Patent No. 229,205, dated June 22, 1880.

Application filed February 14, 1880.

To all whom it may concern:

Be it known that we, SAMUEL It. THOMP- SON, of Brookline, in the county of Norfolk and State of Massachusetts, and SAMUEL W. JOHNSON, of West Medford, county of MiddleseX, and State aforesaid, have invented certain Improvements in Bark-Cutting Machines, of which the following is a specification.

This invention relates to machines having rotary cutters for cutting or reducing bark for tanners use; and it has for its object, first, to provide certain improvements in the rotary cutter, whereby the machine is-enabled to run at a lower rate of speed and with less wear and jar than heretofore; secondly, to provide improved means for separating coarse fragments of bark from the properly-reduced particles thirdly, to enable the cutter to be readily exposed or uncovered when desired.

To these ends my invention consists in. the

improvements which we will now proceed to describe and claim. Of the accompanying drawings, forming a part of this specification, Figure 1 represents a side elevation of a barkcutting machine embodying my invention. Fig. 2 represents a transverse vertical section of the same. Fig. 2" represents a modification. Fig. 3 represents a section on line a: 00, Fig. 2. Fig. 4. represents a plan view of the rotary cutter. Fig. 5 represents a section on line y 3 ,Fig. 4. Fig. 6 represents a front view of the machine. Fig. 7 represents a side view'with the hopper turned back to expose the cutter. Fig. 8 represents a side .view of the hopper detached.

The sameletters indicate the same parts in all the figures.

In the drawings, A represents the rotary cutter, constituting a part of my invention. This cutter is composed of a cylindrical body and independent teethc a, projecting therefrom, the cutter being preferably formed by placing a series of saws side by side on an arbor, although any other suitable construction may be adopted. the teeth of an ordinary circular saw, and the teeth a are longer-that is, their points project. farther from the axis of the cutter than The teeth a, a are shaped like the points of the teeth a, the difference in length being preferably about one-eighth of an inch. The teeth are arranged in rows extending longitudinally of the body of the cut ter, each longitudinal row being composed of alternating longer and shorter teeth, as shown in Fig. 4. The teeth forming the longitudinal rows are placed side by side, each in contact with the next, so that there are no vacant spaces between them; hence the longitudinal rows are continuous. The teeth are also arranged in rows extending around the periphery of the cutter, the teeth of each saw constituting a peripheral row. We prefer to make these peripheral rows of alternating longer and shorter teeth, as shown in Figs. 4 and 5. By this arrangement of teeth each tooth is enabled to separate an independent fragment from a sheet or piece of bark, and no part of the end of the bark is left untouched by each longitudinal row of teeth, as would be the case if the teeth were separated by intervening spaces, as has been usual heretofore. When the teeth are so separated the cutter has to be driven very rapidly, in order that the portions of the bark untouched by one row of teeth may be properly cut by the succeeding rows, and unless the cutter is driven very rapidly its tendencyis to break or crush off the tongues left on the end of the bark by the vacant spaces between the preceding teeth, the result being the detachment of fragments too large to be properly leached and the reduction of a portion of the bark to powder, which is always objectionable in-the reduced bark, because it accumulates in masses and resists the action of water in leaching.

\Ve have found by practice that our improved cutter performs good work, and does not require to be driven so rapidly as the cutters heretofore used, so that less power is required to drive the cutter and less jar and vibration are caused by the operation of the machine.

It will be seen that while the longitudinal rows are continuous, so that they act on all parts of the end of a sheet or piece of bark, the alternating longer and shorter teeth com posing the longitudinal rows insure the separation of the bark removed into uniform particles of the proper size for leaching.

The arbor of the cutter is supported in suitable bearings on the top of a supportingframe, B, which incloses a chute, (3, below the cutter. In this chute is located a shaft, D, which is journa-led in a movable frame, E, which is adapted to slide into and out of the frame B.v

The shaft D is provided with a series of peripheral collars, F, and intervening peripheral grooves or pockets, G, about half an inch wide, and having partitions H H. The interior of the frame E forms a part of the chute U, and is about equal in width to the diameter of the collars, so that when pieces of bark too large to enter the pockets G fall from the cutter they will be arrested by the collars, the properlyreduced curtin gs falling into the'pockets G and being carried over by the partitions H as the shaft revolves.

The pieces arrested by the collars F may be cut or broken up by the joint action of teeth I, formed on said collars, and a shoulder, J, formed on one of the side blocks of the frame E, said shoulder having grooves K, through which the collars pass. The pieces of bark are arrested by the shoulder J, while the teeth I cut or break them. If desired, however, the shoulderJ and teeth I maybe dispensed with, and the shaft D may be located nearer the cutter, so that pieces of bark arrested by the collars F will be caught up by the cutter as they accumulate and carried over thereby to the bed-plate, hereinafter described, to be reduced.

The removable frame E enables the shaft D to be removed for repairs. The shaftD has a pulley, L, on one end, which is belted to a pulley, M, on the arbor of the cutter.

N represents whatI term the hopper-frame, which is located at the top of the frame B, and is prm'ided with lugs I, extending downwardly and pivoted at O 0 to the frameB. This frame N incloses and covers the cutter when in operative position, and has the general form of a hopper. One side of the frame N is inclined and properly arranged with reference to the cutter to constitute a bed-plate, Q, to support the bark as it is presented to the cutter. This bed-plate does not extend in one piece to the cutter, but is supplemented by a movable steel plate, R. Two methods of supporting and moving the plateRare shown, respectively, in Figs. 2 and 2". In the former the plate R is attached to an inclined plate, S, which forms a part of the frame B. The plate R in this case is at right angles with the bed-plate, and is attached to the plate S by a bolt, T, passing through a slot in the plate R. Screws V, passing through a flange, W, on the plate S, serve to move the plate R at right angles to the plane of the bed-plate when the bolt T is lowcred.

In Fig. 2 the plateR is attached by a bolt,

teeth of each adjacent row, as

T, to an inclined plate, S, forminga part of the frame B. The bolt T is attached to the plate R and passes through a slot in the plate S. In this case the plate R is movable in the same plane as the bed-plate. In either case the plate R constitutes an adjustable terminus of the bed plate, which receives the wear caused by the action of the cutter on the bark, and is capable of being adjusted to compensate for wear. 7

The hopper frame N is provided with a feed-roll, U, which is positively rotated by a sprocket-wheel, N, connected by a chain, N to a wheel, N, which is journaled on a shaft, N projecting from a plate, N attached to the side of the hopper-frame. The feed-roll U is journaled in weighted arms U U, which are pivoted at u u to the sides of the hopperframe, and are adapted to oscillate and permit the feed-roll to move laterally.

By pivoting the hopper-frame to the supporting-frame B, as described, and supporting the feed-roll and its driving mechanism on the hopper-frame, we are enabled to readily expose 0 i the cutter by swinging back the hopper-frame, as shown in Fig. 7, whenever the cutter is to be removed or repaired. We'thus avoid the labor and delay usually incident to removing the hopper and other mechanism to enable access to be had to the cutter.

The shaft of the feed-roll projects through slots U in the sides of the hopper. The sides of the hopper have vertical openings U extending from the slots U, to permit the upward movement of the shaft of the feed-roll when it is desired to remove the latter. The openings U are closed when the feed-roll is in place by pieces U, attached to the cover U of the hopper, said cover being detachable with v the pieces U F represents a friction -roll located in an opening in the bed-plate.

We claim as our invention 1. In a bark-cutting machine, a rotary cut-' ter having alternating long and short teeth arranged in longitudinal rows, the alternating long and short teeth of said rows being respectively alternated with the short and long set forth.

2. In combination with a rotary cutter having independent teeth and a chute or passage leading from such cutter, a rotary shaft, D, located in the chute, having a series of collars, F, and intervening pockets, G, the diameter of said collars being about equal to the width of the chute, so that they arrest all fragments too small to enter the pockets, the latter carrying zftway the properly-reduced particles, as set orth.

3. The rotary shaft D, having collars F, intervenin g pockets, G, and teeth I I on said collars, combined with the fixed block having a grooved shoulder, J, as set forth.

4. In combination with the chute or passage 0 O and the shaft D, having collars F and pockets G, the sliding frame F, supporting the shaft D,and enabling said shaft to be removed from names to this specification, in the presence of 10 the machine, as set forth. two subscribing witnesses, this 9th day of Feb- 5. The combination of a frame or base, B, ruary, A. D. 1880. supporting a cutter at its top, the hopper- 5 frame having the feed-r011 U, inclined bedplate Q, and lugs P, pivoted to the frame B, so v as to permit the hopper-frame and feed-roll to Witnesses:

be turned back, as set forth. E. B. FAIRGHILD,

In testimony whereof We have signed our 0. F. BROWN. 

